We already know that bonds are especially sensitive to economic data right now, and we knew that today offered an uncommonly condensed schedule with several big ticket market movers arriving on the same day. We even suspected that yesterday's seemingly inexplicable weakness could have been the market's way of bracing for the risk that this morning's data would prompt more selling. As it happened, this morning's data did exactly that, and then some.
Bonds seem most concerned with the ADP employment data (497k vs 228k f'cast). While it's far from a perfect predictor, it speaks to the risk of a similar beat in the big jobs report tomorrow. The result is the typical "Fed accommodation trade" with stocks and bonds losing ground together.